In 1965, neuroscientist Margot Sharpe meets Elihu Hoopes: the "man without a shadow," who will be known, in time, as the most-studied and most famous amnesiac in history. A vicious infection has clouded anything beyond the last seventy seconds just beyond the fog of memory. Over the course of thirty years, the two embark on mirrored journeys of self-discovery: Margot, enthralled by her charming, mysterious, and deeply lonely patient, as well as her...